Since international consumers are looking for sustainable consumption of food safety, quality and traceability, certification schemes have emerged such as ASC. The case study was carried out at Hoa Nghia cooperative (HNC), Soc Trang province, Vietnam, the first intensive shrimp cooperative being awarded ASC certification in Vietnam, with objective to clarify operation of the cooperative in ASC certified process. HNC was established in 2003 with the medium current size of 19 members and 66.5 ha of shrimp culture. VietGAP was applied from 2014 as a premise to move up ASC and being awarded certification in June 2017. The auditing process was supported by World Wild Fund (WWF-VN) from early of 2015 with the participation of processing company (Stapimex – Soc Trang), international buyer (Nordic Seafood – Denmark), local authorities, independent assessment party (Control Union) and shrimp farmers. The total certified process costed $76,220US, equal to $0.22US/kg, of which, farmers contributed the most at 66.5% ($0.14US/kg) but auditing cost paid by processing company. Farmers are required to meet quality requirement for ASC products regulated in farm contract and getting total premium price of $0.17US. Thus, ASC created financial efficiency for farmers in condition of receiving support from relevant organizations and it should be replicated with the improvement in binding of farm contracts to avoid breaking easier for the further cooperatives